1. Field of the Invention
The present invention pertains to voltage waveform generation systems and more particularly to the digital generation of synthetic alternating current voltage waveforms in the audio frequency range.
2. Related Prior Art
Digitally-synthesized sine-wave sources have become commonplace in metrology laboratories in recent years, particularly where a precise knowledge of the phase angle between two waveforms is re Impedance and power bridges, as well as phase angle rely on waveform synthesis techniques to achieve state-of-the-art accuracy. The approach has been applied to ac-voltage with some success; however, imperfections in the steps used to generate the waveforms have limited the ability to calculate the rms value of the ac signal based on a knowledge of the static voltage of each step. Transient energy due to waveform aberrations at the step transitions (often referred to as "glitches") adds to the signal power making it difficult to predict the rms value accurately.